There are various prior art image processing and computer vision systems which acquire and/or process images of a scene. (Generally, a scene includes a background and one or more objects.) Typically, in these systems, an analog image from a camera is converted to a discrete representation by dividing the picture into a fixed number of locations called picture elements, or pixels, and quantizing the brightness of the image at those picture elements into a fixed number of values. Thus, much of the prior art develops a digital image of the actual image or scene and then processes the digital image using a computer. This processing, also called image processing or computer vision, includes modifying the scene image or obtaining properties from the scene image such as the identity or location of the object in the scene.
During the image processing of the scene, the the object (or objects) that is (are) of interest are imaged along with the scene surroundings. These surroundings are called the background. The background is usually further away from the camera than the object(s) of interest. In some types of image processing it is necessary to separate the object(s) image from the background image of the scene. This separation is called figure/ground separation or segmentation.
Objects in the scene are illuminated when light falls on the object(s). Ambient illumination is the illumination due to light sources occurring in the environment such as the sun outdoors and room lights indoors. Thus ambient illumination is illumination from any light source except the special lights used specifically for imaging an object. Some illuminating light is reflected from the object(s). Some reflected light may be glare (also called specular reflection) which is the high amount of light reflected off a shiny object. The color of the glare is mostly that of the illuminating light (as opposed to the natural color of the object).